This invention relates to a terminal and a connector, and more particularly to an improved press-contacting terminal having a wire press-contacting portion with which a wire is press-contacted in such a manner that the wire extends in a direction perpendicular to a terminal fitting direction.
Also, this invention relates to a connector having a housing in which a plurality of terminals, connected respectively to wires, are received, and more particularly to such a connector in which an electrical connection of each terminal can be checked by bringing a probe of a tester into contact with the terminal from the outside of the housing.
One related press-contacting metal terminal is formed by cutting and bending an electrically-conductive metal sheet, and this metal terminal has a narrow, elongated box-like body having a uniform width over an entire length thereof (see, for example, JP-A-10-294138, especially, pages 2 and 3, FIG. 1).
As shown in FIG. 23, a front portion (left-side portion in FIG. 23) of such a press-contacting metal terminal 100 is formed into a terminal connecting portion 110 for connection to a mating metal terminal, while a rear portion thereof (right-side portion in FIG. 23) is formed into a wire press-contacting portion 120 with which a wire D can be press-contacted.
The terminal connecting portion 110 is formed by winding a relevant portion of a metal sheet into a rectangular tubular shape having four corner portions 111, with end portions of this metal sheet portion superposed together at a top wall portion of this terminal connecting portion. A resilient contact piece portion 112 for resilient contact with a mating connection metal terminal is provided within this terminal connecting portion.
The wire press-contacting portion 120 is also formed by winding a relevant portion of the metal sheet into a rectangular tubular shape having four corner portions 121. Grooves 123 are formed respectively in rear end portions of upper and lower plates 122U and 122L to respectively provide a pair of press-contacting blades 124 with which the wire D can be press-contacted. A blade width of the pair of press-contacting blades 124 is generally equal to the width of the rectangular tubular body.
There is known a related press-contacting connector which includes a plurality of press-contacting metal terminals as described above, and a connector housing for receiving these press-contacting metal terminals (see, for example, JP-A-11-191443, especially, pages 2 and 3, FIG. 8.
As shown in FIG. 24, such a press-contacting connector 130 includes a plurality of press-contacting metal terminals 100 as described above, and a connector housing 140 for receiving the press-contacting metal terminals 100.
The connector housing 140 includes a plurality of terminal receiving chambers 141 for respectively receiving the press-contacting metal terminals 140 in a juxtaposed manner. Reception portions 142a and 142b are formed within each terminal receiving chamber 141, and are disposed at a generally central portion of the terminal receiving chamber 141 in a terminal inserting direction (in a left-hand direction in FIG. 24).
When the wire D is press-contacted with the pair of press-contacting blades 124 of the press-contacting metal terminal 100 inserted in the terminal receiving chamber 141, abutment portions 101a and 101b, formed respectively at the upper and lower plates 122U and 122L of the press-contacting metal terminal 100, are brought into abutting engagement with the reception portions 142a and 142b, respectively, so that a pushing force is received.
Therefore, the deformation of the press-contacting metal terminal 100 is prevented as compared with the case where such a pushing force is received by a front end portion of a press-contacting metal terminal.
In recent years, with a compact design of electrical parts, a compact design of the press-contacting metal terminal 100 as well as a compact design of the press-contacting connector 130 has been desired. However, the blade width of the pair of press-contacting blades 124 is equal to the width of the press-contacting metal terminal 100 as described above, and the compact design is limited in connection with the size of the wire D to be press-contacted with the press-contacting metal terminal.
And besides, there is encountered a problem that the strength of the press-contacting blades decreases with the compact design of the press-contacting metal terminal, so that the press-contacting force is lowered.
Furthermore, when forming the press-contacting metal terminal 100 having the box-like shape as described above, those portions of the metal sheet which are to be formed respectively into the corner portions 121 are integrally bent in parallel relation to the adjacent grooves 123, so that the grooves 123 are spread, which invites a problem that the precision of working of the press-contacting blades 124 is lowered.
In the press-contacting connector 130, when the wire D is press-contacted with the pair of press-contacting blades 124, the abutment portions 101a and 101b of the press-contacting metal terminal 100 abut respectively against the reception portions 142a and 142b of the connector housing 140, and are supported by them, respectively. However, the thickness of the abutment portions 101a and 101b can only be made equal to or about twice larger than the sheet thickness, and therefore there is a possibility that upon application of the pushing force, the abutment portions 101a and 101b cut into the reception portions 142a and 142b, respectively, so that the connector housing 140 is subjected to chipping, deformation or the like.
Also, heretofore, electrical parts, electrical devices, control boards, etc., mounted on a vehicle or the like in spaced relation to each other, are electrically connected by a wire harness including a plurality of wire groups in which predetermined connectors are beforehand attached to predetermined ones of these wires.
In such a wire harness, when a trouble develops in any of the connectors, this connector, together with its outwardly-extending wires, is cut off from the wire harness, and an exchange-purpose connector, having wires beforehand extended outwardly therefrom, is used, in which case the wires of the exchange-purpose connector are connected respectively to corresponding wires of the wire harness, thereby achieving the recovery. In such a case, it is necessary to confirm whether or not the original wires of the wire harness are properly connected respectively to the wires of the exchange-purpose connector.
In recent years, with the use of an increased number of electrical parts and control circuits, there is a tendency for connectors to receive an increased number of terminals therein, and the receiving density increases, and therefore a strict dimensional control has now been imposed on the terminals.
Therefore, for example, when checking an electrical connection of the terminal, it is necessary to avoid bringing a probe of a tester into direct contact with an electrical contact portion of the terminal. Therefore, there has been proposed the type of connector in which an electrical connection of each terminal can be checked without bringing such a probe into contact with the electrical contact portion.
In a connector 201 shown in FIG. 25, detection holes 209, corresponding respectively to cavities 207, are formed through a rear portion of a lower wall 205 of a housing 203. A lower metal wall (lower surface plate) 213 of each press-contacting terminal 211 is opposed to the corresponding detection hole 209, and the inner side of the detection hole 9 is closed by the lower surface plate 213 of the press-contacting terminal 211.
In this connector 201, a tester rod T can be inserted into the detection hole 209 in the housing 203, and can be brought into abutting engagement with the lower surface plate 213 of the press-contacting terminal 211 for checking an electrical connection of the terminal (refer to JP-A-11-204227).
In many cases, connectors, used for a wire harness, are molded of a resin material since in addition to insulating properties, an impact resistance, moldability and a lightweight design can be obtained. Therefore, there are occasions when the configuration of the connector is limited by the direction of removal of the molded connector from a mold.
The direction of connection of the above related connector 201 to a mating connector and the direction of insertion of the terminals into the connector 101 coincide with each other, that is, are the same direction indicated by arrow “a” in FIG. 25. Therefore, the direction of removal of the connector from the mold is the same direction “a”.
In the above connector, however, the detection holes 9, corresponding respectively to the cavities, are formed through the wall in a direction perpendicular to the mold-removing direction. Therefore, because of its structure, the mold need to include a slide mold, and therefore is complicated in structure. As a result, there was a disadvantage that the cost of the mold increased.
To deal with this problem, for example, the provision of the detection holes was omitted, and a tester rod was inserted through a wire lead-out hole in the rear end of the connector, and was brought into abutting engagement with the metal terminal so as to effect an electrical connection check. In this case, however, the wire interfered with the tester rod, and therefore the operation was difficult.
Particularly when each wire was bent into a crank-shape at the wire lead-out hole by an attached cover as in the connector of FIG. 25, the test rod could not be inserted into the wire lead-out hole, and therefore must be inserted into a cavity opening formed in the front end of the connector, and as a result there was a fear that the terminal was damaged.